This happens because RenderTransformOrigin property is under a FrameworkElement.RenderTransform property if it's a TransfromGroup.
The ElementTreeItem::FindProperty doesn't try to find "RenderTransformOrigin" under a "FrameworkElement.RenderTransform".
Because of that, the FindProperty returns a nullptr and thus a Property value cannot be refreshed after a UpdatePropertyCommand..

The TransformGroup::FindSubproperty implements a check for RenderTransformOrigin, but the request is never forwarded from ElementTreeItem::FindProperty to TransformGroup::FindSubproperty.

It keeps happening when the timeline is present, as seen here: https://youtu.be/hEsC0P0pmuA?feature=shared&t=101

In the last video there was no problem at all. I think that we should be closing this.

For me, it even updates when it's animated.. I am going to close this for the moment, but if you find it still happening, please do reopen it.